Apparatus for drying yarn



June 1941- J. UYTENBOGAART ETAL 2,244,745

APPARATUS FOR DRYING YARN Original Filed Aug. 11, 1937 2 Sheets-Sheet 1 Fig .1. TF TF T T awe/Mow Johannes ((yfen ogaarf Car/ A Gram W m #ZWW FBecZS/Y/ca/ June 10, 1941.

J. UYTENBOGAART ETAL APPARATUS FOR DRYING YARN Original Filed Aug. 11, 1937 D 2 Sheets-Sheet 2 nn 6 "I 5 m w N S I a W 0' ""l s \k 5. We

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Patented June 10, 1941 APPARATUS FOR DRYING YARN Johannes Uytenbogaart, Wassenaar, Netherlands,

and Carl F. Gram, Eliaabethton, 'lenn., assignore to North American Rayon Corporation, New York, N. 'Y., a corporation of Delaware Original application August m, 1937, Serial No.

Divided and this applieation'Auguat 31, 1938, Serial No. 227,832

3 Claims.

The present invention relates 'to the heating of rotating surfacesbut more specifically has for its object to provide a heating element for thread conveying rollers whereby yarn or thread conveyed on such rollers may be uniformly and thoroughly dried during their passage thereover.

The device is particularly adapted for use in machines usedin the continuous production of artificial silk. In machines such as these the filaments are extruded through a precipitating bath and conveyed to rollers over which theypass in anapproximately helical path. The filaments may be given the diflerent wet-treatments.necessary while on the rollers such as desulphurizing, deacidifying, etc. and immediately. thereafter, and while still on the'same rollers or when passed to otherrollers, dried.

For the continuous manufacture of artificial filaments groups of rollers, two or more, may be employed, The rollers are so arranged in their relation to one another that the thread is automatically conveyed inan approximately helical path from one end of the said rollers to the other end thereof. Apparatus such as the above described is disclosed and illustrated in a copending application, Serial No. 730,662, filed'June 14',

dried, a serious consequence particularlyin the manufacture of artificial silk.

Another feature of applicants invention resides in so designing the heating element that the greatest amount of heat contacts the thread immediately after the after-treatment and while the threads contain the greatest amount of moisture. As the threads pass along the heating zone decreasing heat is applied as the threads lose their moisture thus resulting in a more uniformly dried thread. A further advantage of this idea of decreasing the heat as the moisture content of the filaments decreases is that it is less'likely that damage will result to the threads which became of a decreasing moisture content become more susceptible to heat damage. Also by reducing the temperaturedrop, or better, maintaining a fairly constant decrease in temperature throughout the drying zone, less internal strains in the filaments result.

It is therefore one object of the present inventionto devise a heating element for rotating surfaces which does not rotate with the surface thus heated.

Another object of the present invention is to devise a stationary heating element for the inte- 1934, and entitled, Process for treating artificial the filaments takes place on the u r. roller at' its upper end. A gas flame is used to heat the rotating rollers at a point with which the filaments are not at the moment of application of the heat, in contact. This method of heating has proven quite satisfactory in those localities where gas is available. In this invention, however, it is proposed to use an electrical heating element for the drying of the threads.

Heretofore, where any electrical elements have been used for heating the interior of rotating surfaces a great disadvantage has resulted due to the fact that a rotating contact must be used. With such contacting means the'passage of current therethrough k not uniform and they have the additional drawback that wear quickly resuits and replacement of the worn contacts must be made. Further, during the wearing process the fiow of current becomes even more irregular, resulting in yarn which has not been uniformly rior of rotating cylinders which may quickly and easily be removed and replaced without the necessity of stopping production operations.

Still another object of the present invention is to devise a heating element and method which will dry the threads uniformly and with lss danger of damage caused by heat treatment.

These and other'objects will in part become obvious and will in part be p inted out in the following specification and appended claims when taken in conjunction with the attached drawings, in which:

Fig. 1 is a side elevation of a portion of a pair of spaced cylinders with the filaments passing thereover and the novel heating element comprising the invention illustrated in operative position;

Fig. 2 is an end elevation of the part shown in Fig. 1,

Fig. 3 is an enlarged vertical section-taken on the line H of Fig. 2.

The cylinder i has extending therein the heating elementi. The cylinders l and 2 are rotated by any suitable driving mechanism (not shown).

Adjacent the cylinder l'is mounted a support 5 which serves the double purpose of carrying the power conduit wires and supporting the heating element 4. Mounted on the support 5 is a bracket member 'I which carries the power outlet receptacle 8 and has formed therein in axial alinement with said power outlet 8 a socket 8.

The heating element 4 comprises a hollow bracket arm l2 which carries connecting wires l3. At one end of the bracket 12 is formed a socketed extension l5 which carries 'a plug ill having the usual contact members H. The support 5, bracket member l, and bracket arm. l2

. comprise stationary supporting means positioned between cylinders i and 2, and having a portion extending to a position opposite the unsupported end of cylinder l.

The socketed extension I E carrying the plug I0 is removably mounted in the socket 9 of the bracket 1 thereby forming the electrical contact and mounting means.

Formed at the opposite end of the bracket I! are radial supporting arms IS on which is mounted an insulating disc I1 insulated from the arms l6 which may be of asbestos and forms a heat shield H. The shield l1 fits within the inner circumferences of the hollow cylinder 1 and out of contact therewith. This heat shield acts to keep the heat within the cylinder thereby decreasing the amount of heat lost.

Mounted on the shield disc I! is a bracket It to which is bolted at 20 the conical support is of the resistance coil H.

The ends 2| and 22 of the resistance coil H are attached to terminals 23 and 24 to which one end the connecting wires l3 are attached. The other ends of the wires it lead into the plug it.

A peep-hole 25 is bored in the disc i! so that the operator of the machine may ascertain at any time, without removal of the heating element, whether the element is operating.

. As hereinbefore pointed out, the heating element support I9 is tapered so that at one end there is a greater heat intensity than at the other end of the heating zone, and the heating element I extends lengthwise within the cylin der l in generally coaxial alinement with its axis of rotation.

The threads 3 as they begin to pass over the heated portion of the cylinder i are in wet condition and therefore less susceptible to heat. As the filaments pass along the heated portion oi the roller and gradually lose their moisture con-'- tent there is less need for heat and the threads are less protected. 1

By tapering the heating element as illustrated in the drawings the source of heat is nearer to the wall of the cylinder and the coil is longer at that point where the threads are carrying the greatest amount of moisture, and the threads therefore receive the greatest amount of heat.

As the threads pass along the heated surface of the cylinder, due to the tapering of the heating element inwardly, less heat is emitted and ill cam-m reaches the cylinder thus decreasing the heat of drying as the threads decrease in moisture content. I

The rotatable cylinder 2 cooperating with cylinder I containing the heating element 4 constitutes means for directing or advancing the threads progressively along the heated cylinder surface in the direction of the smaller end of thetapered heating element.

By decreasing the amount of heat as the threads or filaments lose their moisture content a more advantageous drying results with 1e chance of damage to the filaments.

It is to be understood that the form of the invention, herewith shown and described, is to be taken as a preferred example of the same. and

158,496, entitled Process and apparatus for drying yarn, filed August 11, 1937.

What is claimed is:

1. Apparatus for drying a continuous length of yarn, thread, or the like, comprising, incombination, a rotatable cylinder, a tapered heating element disposed lengthwise within the rotatable cylinder and in generally coaxial spaced relation thereto, and means for directing 'the yarn, thread, or the like over the said rotatable cylinder and progressively along its surface from one end toward the other and in the direction of the smaller end of the tapered heating element.

2. An apparatus for use in the continuous drying of yarn, thread, or the like, comprising, in combination, a pair of spaced rotatable cylinders, and a stationary tapered heating element extending into one of said cylinders inaxial alinernent with the axis of rotation thereof, saidcylinders being arranged to move the yarn, thread, or the like, along the cylinders in an approximately helical path advancing toward the smaller end of the tapered heating element.

3. An apparatus for use in the continuous drying of yarn, thread, or the like, comprising, in combination, a pair of spaced rotatable cylinders having adjacent unsupported ends, stationary supporting means positioned between said cylinders and having a portion extending to a position opposite the unsupported end of oneof said cylinders, and a conical heating element mounted by its smaller end on the portion of said supporting means opposite the end of one of said cylinders and extending lengthwise within that cylinder in coaxial spac relation thereto, said cylinders being arranged to move the yarn, thread, or the like, in an approximately helical path toward their unsupported ends.

JOHANNES UY'I'ENBOGAART. CARL F. GRAM. 

